[AUDITORY] Software/code for insertion of a large number of triggers

Dear Pragati Rao,

Enclosed is a tutorial review with links to code (slides 146-174 are most relevant). The .wav cue approach to triggers is most effective with NBS presentation, though I have known people have problems with there being a dynamics to the port code onset to event onset delay and its jitter through the course of the paradigm, particularly with large numbers of port codes. This can happen even when the timing seems fine at first. Initial clues to this may be seen with a dry run of the paradigm when looking at the uncertainties in the log file  Recommended is to record a trigger channel and the sound signal via multichannel oscilloscope for the whole dry run and then analyze this to assay if there is such a dynamics. You do want that delay to be constant within limits that are suited to your EEG sample rate and the ERP deflections of interest.

Best regards,

Tom Campbell.

Date: Fri, 6 Sep 2013 08:36:10 +1000
From: Pragati Rao <pragatir@xxxxxxxxx>
Subject: Software/code for insertion of a large number of triggers.

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Dear All,

I have to insert triggers for an EEG experiment (almost 3000 triggers) into
a wav file. Adobe audition or Goldwave can be used for this purpose. The
process is very time consuming. Does anyone know of a more time-efficient
way of doing this? Perhaps a MATLAB code?

I tried getting the sound presentation software to send cue events, but I
was advised by presentation (neurobehavioral system) to have this trigger
information within the sound file (so that timing information is precise).

Any help is appreciated.

Thanks,
Pragati Rao,
PhD Candidate and Research Audiologist,
Room 1.612, Level 1,
Australian Hearing Hub,
16 University Avenue,
Macquarie University,
NSW 2109

http://www.hearingcrc.org/people/pragati-mandikal-vasuki

http://www.ling.mq.edu.au/cll/team.html